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arXiv · 2306.09454

Analytical Evaluation of Elastic Lepton-Proton Two-Photon Exchange in Chiral Perturbation Theory

Poonam Choudhary·Udit Raha·Fred Myhrer·Dipankar Chakrabarti
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Abstract

We present an exact evaluation of the two-photon exchange contribution to the elastic lepton-proton scattering process at low-energies using heavy baryon chiral perturbation theory. The evaluation is performed including next-to-leading order accuracy. This exact analytical evaluation contains all soft and hard two-photon exchanges and we identify the contributions missing in a soft-photon approximation approach. We evaluate the infrared divergent four-point box diagrams analytically using dimensional regularization. We also emphasize the differences between muon-proton and electron-proton scatterings relevant to the MUSE kinematics due to lepton mass differences.

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Poonam Choudhary, Udit Raha, Fred Myhrer, Dipankar Chakrabarti. 2023-06-15. Analytical Evaluation of Elastic Lepton-Proton Two-Photon Exchange in Chiral Perturbation Theory. https://arxiv.org/abs/2306.09454

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